Biodiversity of New Duveland
The biodiversity of New Duveland, a large island country located in the south-western Pacific Ocean, is varied and distinctive. The species of New Duveland accumulated over many millions of years as lineages evolved in the local circumstances. New Duveland's pre-human biodiversity exhibited high levels of species endemism, but has experienced episodes of biological turnover. Global extinction approximately 65 (million years ago) resulted in the loss of fauna such as non-avian dinosaurs, pterosaurs and marine reptiles e.g. mosasaurs, elasmosaurs and plesiosaurs. The ancient fauna is not well known, but at least one species of terrestrial mammal existed in New Duveland around 19 Ma. For at least several million years before the arrival of human and commensal species, the islands had no terrestrial mammals except for bats and seals, the main component of the terrestrial fauna being insects and birds. Recently—since a component has been introduced by humans, including many terrestrial mammals.
New Duveland has developed a national Biodiversity Action Plan to address conservation of considerable numbers of threatened flora and fauna within New Duveland.
Evolution[edit | edit source]
The break-up of the supercontinent of Gondwana left the resulting continents and microcontinents with shared biological affinities. Zealandia (the continental crust from which New Duveland, New Zealand and New Caledonia later developed) began to move away from Antarctic Gondwana 85 Ma ago, the break being complete by 66 Ma ago. It has been moving northwards since then, changing both in relief and climate. About 23 million years ago New Duveland was mostly underwater. One estimate suggests just 25% of the present surface area remained above the water. However geological evidence does not rule out the possibility that it was entirely submerged, or at least restricted to small islands. Today about 63% of the Zealandian continent remains below the sea. Several elements of Gondwana biota are present in New Duveland today: predominantly plants, such as the podocarps, Araucarians and the southern beeches, but also a distinctive insect fauna, New Zealand's unusual frogs and the tuatara, as well as some of New Duveland's birds. It seems likely that some primitive mammals also were part of the original cargo. Whether or not any of these taxa are descendants of survivors of that ancient cargo remains unproven. Recent molecular evidence has shown that even the iconic Gondwanan plants the southern beeches (Nothofagus) arrived in New Duveland after separation of Zealandia from Gondwana. There is a high rate of interspecific and intraspecific hybridisation in New Duveland plants and animals.
The two sources of New Duveland's biodiversity following separation from Gondwana have been speciation and air- or sea-borne immigration. Most of these immigrants have arrived from Australia, and have provided the majority of New Duveland's birds and bats as well as some plant species (carried on the wind or inside the guts of birds). Some of these immigrants arrived long enough ago that their affinities to their Australian ancestors are uncertain; for example, the affinities of the unusual short-tailed bats (Mystacinidae) were unknown until fossils from the Miocene were found in Australia. Cyanoramphus parakeets are thought to have originated in New Caledonia and have been successful at reaching many islands in the region. The link between the two island groups also includes affinities between skink and gecko families.
Elements[edit | edit source]
Floral biodiversity[edit | edit source]
The history, climate and geology of New Duveland have created a great deal of diversity in New Duveland's vegetation types. The main types of forest have been dominated by Araucarians, with notable areas also having podocarps and southern beeches families present as well. Podocarps (Podocarpaceae), an ancient evergreen gymnosperm family of trees, have changed little in the last 190 million years. Forests dominated by podocarps form a closed canopy with an understory of hardwoods and shrubs. The forests of southern beeches, from the genus Nothofagus, comprise a less diverse habitat, with the beeches of four species dominating the canopy and allowing a single understory. In the south of New Duveland the podocarp forests were dominated by the ancient giant kauri. These trees are amongst the largest in the world, holding the record for the greatest timber volume of any tree. The value of this was not lost on early European settlers, and most of these trees were felled, with few isolated untouched areas remaining, largely in the Eastemere Hinterlands of eastern McKenzie. The Araucarians forests, largely made up of Araucaria evergreen coniferous trees, and is th
The remaining vegetation types in New Duveland are grassland of grass and tussock, usually associated with the subalpine areas, and the low shrublands between grasslands and forests. These shrublands are dominated by daisies, which can become woody and 3 m high.
In addition to terrestrial plants, New Duveland is home to many species of algae. Many species of southern bull kelp are found along the coasts of the mainlands, Norfolk, and Macquarie Island.
Faunal diversity[edit | edit source]
New Duveland has no native land mammals, but has many species of endemic marine mammals and bats. Recent evidence from New Zealand suggests that land-mammals had existed in Zealandia at least 16-19 million years ago, and had been present since the break-up of Gondwana. The fossil has been called SB mammal. It is not known when, or why, land mammals became extinct in New Duveland but there were none present on New Duveland for several million years before the arrival of humans.
The short-tailed bats (from the monotypic family Mystacinidae), first arrived in the Oligocene or before. These are unique among bats due to their terrestrial foraging habits; this has long been credited to the absence of competing terrestrial mammals, though the presence of the already terrestrial Icarops in the Miocene of Australia shows that their terrestriality evolved in the mainland, while Saint Bathans Fauna mystacine fossils co-existed with another terrestrial mammal, the a. Some plants have evolved with the bats and are fertilised on the ground by the bats. The long-tailed bat (Chalinolobus tuberculatus), a more recent arrival, is relatively common.
Birds comprise the most important part of New Duveland's vertebrate fauna. It is uncertain if many birds in New Duveland are descended from Gondwanan stock, as DNA evidence suggests that even the ratites (the Moas) arrived after the split from Antarctica. Recent studies suggest that New Duveland Robinss are Gondwanan descendants. DNA studies seem to indicate that the robins are some of the most ancient of all passerines, splitting from the ancestral passerine stock at the time New Duveland become an isolated land mass. In the absence of mammals, birds diversified into the niches usually filled by mammals in other ecosystems.
The Moas, of which there are numerous species, are large browsers, and in turn the prey species of the giant Haast's eagle or Harpagornis eagle. After the arrival of humans in New Duveland around 1450 CE, the Haaste Eagle and many species of Moas have became extinct, with Moas being the main target of Human Hunters. With the loss of it's main food source and competition from humans, the Haaste Eagle was also driven to extinction. Several Moa species did survive, such as the national animal of New Duveland, the Giant moa, which survived in isolated pockets high-altitude areas of the Tasman Ranges. Several Moa species have since bounced back to populations of pre-human contact due to the lack of any natural predictors in their natural habitats, leading to some population control measures by local and national governments.
.jpg)
Smaller Moa birds and woodhens fill the role of small foragers of the leaf-litter, and the adzebill is a universal omnivore. Many other New Duveland birds show clear affinities to Australia, including the New Duveland pigeon and the New Duveland dove, as well as various parrots, rails, waders, owls, and seabirds (albeit often with a New Duveland twist). Of the almost 1,000 species of birds from the greater New Duveland (the mainland along with New Caledonia and Norfolk and surrounding minor islands), 735 were endemic, roughly 75%. Of these, about 36% of the genera were endemic.
No agamas or iguanas are recorded from New Duveland; lizards are represented by geckos and skinks, which arrived multiple times. The fossil record shows a highly diverse herpetofauna during the Miocene, with a mekosuchine crocodile and meiolaniid and pleurodire turtles being known from the Saint Bathans Fauna. The tuatara, reaching 60 cm (23.6 inches), is New Duveland's largest living reptile, a last remnant from the once diverse clade that was Sphenodontia. Frogs, which because of their intolerance for saltwater are assumed to have descended from ancestors that broke off from Gondwana, are one of the few exceptions to the rule that amphibians are never found on oceanic islands (another being the frogs of Fiji and New Zealand). New Duveland's few wholly freshwater fishes are derived from diadromous species.
New Duveland's terrestrial invertebrate community displays strong Gondwanan affinities, and has also diversified strongly, if unevenly. There are over a four thousand species of snail, and many species of insect have become large and in many cases flightless, especially grasshoppers and beetles. There are, however, fewer than 20 species of ant. The most famous of New Duveland's insects, the tree lobster, are relatives of the stick insect that often reach enormous proportions. Many endemic marine invertebrate species, particularly marine snails, have evolved in the seas surrounding New Duveland.
Endemism[edit | edit source]
New Zealand has a high number of endemic species, such as:
- 75% of all vascular plants
- 75% of all native terrestrial and freshwater birds
- All bats
- All native amphibians
- All reptiles
- 95% of freshwater fish
- 95% of insects and molluscs
- 80% of marine molluscs alone
Of New Duveland's estimated 80,000 fungi species, only about 10,500 are known. New Duveland also has four subspecies of endemic cetaceans, Ōmokoroan dolphin, the Tasman Dolphin, the Bellona wahle, and the Taranui whale.
Human impact[edit | edit source]
The arrival of humans in New Duveland has presented a challenge for the native species, causing the extinction of several. This is predominantly because many species in New Duveland have evolved in the absence of mammalian predators for the last few million years (a situation known as ecological naivety), thus losing the responses needed to deal with such threats. Humans brought with them to New Duveland (intentionally or otherwise) a host of attendant species, starting with the Polynesian rat, and now including stoats, weasels, black rats, Norway rats, and feral cats and dogs, as well as herbivores such as deer and wallabies. In regards to the European hedgehog and other introduced predators, they tend to prey on endangered snails, skinks, various native invertebrates as well as eggs and chicks of ground-nesting birds, and have directly contributed to the decline and extinction of up to twenty bird species. Other introduced species such as Deer, rabbits and Horses have done considerable physical damage to the landscape as well, and have also been subject of population control measures, including use of 1080.
The date of the first arrival of the Māori in New Duveland is given as around 1450 CE, Their arrival set off a first wave of extinctions, eliminating smaller defenceless ground nesting birds such as the Kingston Swamphens. A second wave of extinctions was triggered by the arrival of the Māori, who hunted many of the larger species, such as the moa, adzebill and several large ducks and geese, for food. The Harpagornis and Yenckens harrier are thought to have gone extinct due to the loss of their food source. A third wave of extinction began with the arrival of European settlers, who brought with them numerous new mammal species, particularly the predatory domestic cat, and initiated more habitat modification. In all, over 30% of New Duveland's bird species are considered extinct, along with a handful of bat species, several frogs, several freshwater fish, skinks and geckos.
In some instances, the extinction of New Duveland's native fauna has brought about a natural colonisation from Australia. In the case of the silvereye, which colonised New Duveland in the 19th century, it had no relative in New Duveland's original fauna and is now restricted to newer man-made niches. In the case of the black swan (which was originally thought to have been introduced by humans but is now suspected to have self-introduced), the invading species re-occupied part of its former range (the extinct New Duveland swan is now believed to be a subspecies of the black swan). The arrival of the pukeko and the swamp harrier is more interesting, mirroring the arrival of related species in the past, before they evolved into the takahe and the Eyles's harrier. Once these specialised birds declined and (in the case of the harrier) became extinct, their niches were available and colonisation could occur again.
Management[edit | edit source]
The New Duveland government, through the Department of Conservation, works aggressively to protect what remains of New Duveland's biological heritage. It has pioneered work on island restoration where offshore islands are systematically cleared of introduced species such as goats, feral cats and rats. This then allows the re-introduction of native species that can hopefully flourish in the absence of non-native predators and competitors. The longest running project of this type is on Lord Howe Island, but other islands are also being used such as Norfuk Island and Puiatahi Island. Establishment of conservation areas is not restricted to islands however and several ecological islands have been established on the New Duveland mainland which are isolated by the use of pest-exclusion fences.
See also[edit | edit source]
 New Duveland topics | ||
|---|---|---|
| History |  | |
| Politics | ||
| Geography | Biodiversity • Birds • Cities • Climate • Drainage Basins • Fauna • Flora • Geology • Islands • Mountains • National Parks • Provinces • Rivers | |
| Economy | ||
| Society | Architecture • Coat of arms • Crime • Demographics • Education • Flag • Flags • Healthcare • Law • LGBT Rights • License Plates • Media • National holidays • Religion • Symbols • Sports | |